Human Fetuses Develop Useless Hair

One of my favorite cases of embryological evidence for evolution is the furry human fetus. We are famously known as “naked apes” because, unlike other primates, we don’t have a thick coat of hair. But in fact for one brief period we do—as embryos. Around sixth months after conception, we become completely covered with a fine, downy coat of hair called lanugo. Lanugo is usually shed about a month before birth, when it’s replaced by the more sparsely distributed hair with which we’re born. (Premature infants, however, are sometimes born with lanugo, which soon falls off.) Now, there’s no need for a human embryo to have a transitory coat of hair. After all, it’s a cozy 37 degrees C in the womb. Lanugo can be explained only as a remnant of our primate ancestry: fetal monkeys also develop a coat of hair at about the same stage of development. Their hair, however, doesn’t fall out, but hangs on to become the adult coat. And, like humans, fetal whales also have lanugo, a remnant of when their ancestors lived on land.

Notes:

That appears at the same time in development as it does in Chimpanzees, but then vanishes.

Folksonomies: evolution fetal development recapitulation

Taxonomies:
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/family and parenting/motherhood/pregnancy (0.498807)
/family and parenting/babies and toddlers (0.462268)

Keywords:
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Entities:
Lanugo:Person (0.854982 (negative:-0.315737)), 37 degrees:Quantity (0.854982 (neutral:0.000000))

Concepts:
Embryo (0.970869): dbpedia | freebase | opencyc
Fetus (0.945016): dbpedia | freebase | opencyc
Pregnancy (0.787053): dbpedia | freebase | opencyc
Mammal (0.695250): dbpedia | freebase | opencyc
Embryology (0.647265): dbpedia | freebase | opencyc
Developmental biology (0.633915): dbpedia | freebase
Uterus (0.606302): dbpedia | freebase | opencyc
Primate (0.559315): dbpedia | freebase | opencyc

 Why Evolution Is True
Books, Brochures, and Chapters>Book:  Coyne , Jerry A. (January 22, 2009), Why Evolution Is True, Penguin (Non-Classics), Retrieved on 2011-09-15
Folksonomies: evolution evidence creationism